Intra-articular Autologous Conditioned Plasma Injections Provide Safe and Efficacious Treatment for Knee Osteoarthritis: An FDA-Sanctioned, Randomized, Double-blind, Placebo-controlled Clinical Trial

The Clinical Evidence Behind Biologic Therapies Promoted at Annual Orthopaedic Meetings: A Systematic Review

PURPOSE

The purpose of this study is to systematically evaluate the available clinical data for biologic therapies promoted for articular cartilage defects and osteoarthritis of the knee at the 2016 American Orthopaedic Society for Sports Medicine Meeting (AOSSM) and the 2017 Arthroscopy Association of North America meeting (AANA).

METHODS

Our sample included all exhibitors at the 2016 AOSSM meeting and 2017 AANA meeting. All biologic products marketed at each conference were identified by reviewing exhibition booths and company websites. A systematic review of the clinical data on each product was then completed using PubMed, EMBASE, and the product's own webpage. All clinical peer-reviewed studies with level I-IV evidence were included in the study. Basic science or preclinical studies were excluded.

RESULTS

There were 16 products promoted for biologic therapy for articular cartilage defects or osteoarthritis of the knee at the AOSSM meeting and 11 products promoted at the AANA meeting. A total of 280 articles detailed clinical findings for the articular cartilage products displayed at AOSSM and AANA. Of the 280, there were 36 level I evidence studies, 37 level II evidence studies, 18 level III evidence studies, and 189 level IV evidence studies. Of these articles, 91% were for 4 products. Of all biologic products promoted at the 2 meetings, 65% did not have any peer-reviewed clinical data supporting their use.

CONCLUSION

Overall, many biologic therapies promoted at leading arthroscopy and sports medicine conferences did not have clinical evidence evaluating their use in the peer-reviewed literature. Although scientific advancement requires new technology, orthopaedic surgeons should be cautious about using biologic therapies in their practice with no proven efficacy. There are likely promising new interventions that, with additional scientific research, will be proven efficacious for our patients.

CLINICAL RELEVANCE

This article gives orthopaedic surgeons a detailed example of some of the biologic treatments being offered on the market for the treatment of knee articular cartilage disease. When patients request these treatments, physicians must be able to explain the data supporting their use.

Intra-articular Injection of Platelet-Rich Plasma Is Superior to Hyaluronic Acid or Saline Solution in the Treatment of Mild to Moderate Knee Osteoarthritis: A Randomized, Double-Blind, Triple-Parallel, Placebo-Controlled Clinical Trial

PURPOSE

To prospectively compare the efficacy of intra-articular injections of platelet-rich plasma (PRP) and hyaluronic acid (HA) with a sham control group (normal saline solution [NS]) for knee osteoarthritis in a randomized, dose-controlled, placebo-controlled, double-blind, triple-parallel clinical trial.

METHODS

A total of 87 osteoarthritic knees (53 patients) were randomly assigned to 1 of 3 groups receiving 3 weekly injections of either leukocyte-poor PRP (31 knees), HA (29 knees), or NS (27 knees). The Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) score and International Knee Documentation Committee (IKDC) subjective score were collected at baseline and at 1, 2, 6, and 12 months after treatment. Data were analyzed using generalized estimating equations.

RESULTS

All 3 groups showed statistically significant improvements in both outcome measures at 1 month; however, only the PRP group sustained the significant improvement in both the WOMAC score (63.71 ± 20.67, increased by 21%) and IKDC score (49.93 ± 17.74, increased by 40%) at 12 months. For the intergroup comparison, except for the first month, there was a statistically significant difference between the PRP and NS groups in both scores throughout the study duration (regression coefficients of 8.72 [P = .0015], 7.94 [P = .0155], and 11.92 [P = .0014] at 2, 6, and 12 months, respectively, for WOMAC score, and 9.1 [P = .0001], 10.28 [P = .0002], and 13.97 [P < .0001], respectively, for IKDC score). There was no significant difference in both functional outcomes between the HA and NS groups at any time point. Only the PRP group reached the minimal clinically important difference in the WOMAC score at every evaluation (15%, 21%, 18%, and 21% at 1, 2, 6, and 12 months, respectively) and the minimal clinically important difference in the IKDC score at 6 months (improvement of 11.6).

CONCLUSIONS

Intra-articular injections of leukocyte-poor PRP can provide clinically significant functional improvement for at least 1 year in patients with mild to moderate osteoarthritis of the knee.

LEVEL OF EVIDENCE

Level I, randomized controlled single-center trial.

Platelet-Rich Plasma

Platelet-rich plasma (PRP) is a promising treatment for musculoskeletal maladies and clinical data to date have shown that PRP is safe. However, evidence of its efficacy has been mixed and highly variable depending on the specific indication. Additional future high-quality large clinical trials will be critical in shaping our perspective of this treatment option. The heterogeneity of PRP preparations, both presently and historically, leads sweeping recommendations about its utility impossible to make. This heterogeneity has also made interpreting existing literature more complicated.

Current Clinical Recommendations for Use of Platelet-Rich Plasma

PURPOSE OF REVIEW

This review evaluates current clinical literature on the use of platelet-rich plasma (PRP), including leukocyte-rich PRP (LR-PRP) and leukocyte-poor PRP (LP-PRP), in order to develop evidence-based recommendations for various musculoskeletal indications.

RECENT FINDINGS

Abundant high-quality evidence supports the use of LR-PRP injection for lateral epicondylitis and LP-PRP for osteoarthritis of the knee. Moderate high-quality evidence supports the use of LR-PRP injection for patellar tendinopathy and of PRP injection for plantar fasciitis and donor site pain in patellar tendon graft BTB ACL reconstruction. There is insufficient evidence to routinely recommend PRP for rotator cuff tendinopathy, osteoarthritis of the hip, or high ankle sprains. Current evidence demonstrates a lack of efficacy of PRP for Achilles tendinopathy, muscle injuries, acute fracture or nonunion, surgical augmentation in rotator cuff repair, Achilles tendon repair, and ACL reconstruction. PRP is a promising treatment for some musculoskeletal diseases; however, evidence of its efficacy has been highly variable depending on the specific indication. Additional high-quality clinical trials with longer follow-up will be critical in shaping our perspective of this treatment option.

Platelet-Rich Plasma and the Knee-Applications in Orthopedic Surgery

PURPOSE OF REVIEW

To consolidate and synthesize the most recent evidence on the effects of platelet-rich plasma (PRP) in the knee with respect to osteoarthritis, meniscal injuries, ACL reconstruction, total knee arthroplasty (TKA), and high tibial osteotomy.

RECENT FINDINGS

PRP has been shown to be more beneficial in the context of knee osteoarthritis compared to both placebo and hyaluronic acid. Direct comparison with corticosteroid injections has been sparsely studied. It has also been shown to improve the clinical postoperative course in meniscal injuries and to a lesser extent TKA. Radiographic improvements without clinically significant benefits have been observed with ACL reconstructions treated with PRP. PRP injections may be more beneficial than other current non-surgical management options for specific knee pathologies. Further research should broaden the knowledge of PRP effects on the knee, and identify the type of PRP, growth factor distribution, and route of administration associated with the most benefit.

Clinical Update: Why PRP Should Be Your First Choice for Injection Therapy in Treating Osteoarthritis of the Knee

PURPOSE OF REVIEW

The purpose of this review is to update the reader on the current applications of platelet-rich plasma (PRP) in the treatment of knee osteoarthritis (KOA). This review will focus on PRP's effect on the osteoarthritic joint, how PRP compares to traditional treatments of KOA, and provide clinical feedback on the use of PRP in an orthopedic and sports medicine practice.

RECENT FINDINGS

Recent research into the applications of PRP for KOA has further indicated both the efficacy and safety of PRP treatment. Although research has shown a tendency toward better efficacy at earlier stages of osteoarthritis (OA), evidence exists to indicate positive effects at all stages of OA. In summary, since KOA is an extremely prevalent condition that can be a challenge to treat, it is imperative that safe and effective nonoperative treatment methods be available to individuals that are suffering from this condition.

Platelet-rich plasma versus hyaluronic acid injections for knee osteoarthritis: a propensity-score analysis

BACKGROUND AND AIMS

Intra-articular injections of viscosupplements have been an option in the treatment of knee osteoarthritis. Platelet-rich plasma is an experimental treatment in osteoarthritis. Previous studies have shown that platelet-rich plasma reduces osteoarthritis symptoms in similar proportions as viscosupplements. The aim of this study was to compare platelet-rich plasma versus viscosupplements in terms of symptoms' relief and time to arthroplasty.

MATERIAL AND METHODS

A total of 190 patients included in this retrospective study received either intra-articular injections of platelet-rich plasma (94 patients) or hyaluronic acid (86 patients) between January 2014 and October 2017. Western Ontario and McMaster Universities Osteoarthritis Index, Visual Analogue Scale, and range of motion were measured before injection, at 15 days, 6 months, 12 months, and at last follow-up. We compared outcomes between these two groups using propensity score analysis for risk adjustment in multivariate analysis and for one-to-one matching.

RESULTS

Hyaluronic acid-treated patients experienced a higher arthroplasty rate (36.0% vs 5.3%, p < 0.001), lower range of motion, worse Visual Analogue Scale and Western Ontario and McMaster Universities Osteoarthritis Index scores, and increased risk of any arthroplasty occurrence (log-rank < 0.001) than platelet-rich plasma patients. Cox proportional hazards analysis revealed a tendency to decrease the risk of knee arthroplasty for the patients treated by platelet-rich plasma (hazard ratio = 0.23, 95% confidence interval, 0.05-1.05, p = 0.058). When the treatment method was adjusted for propensity score in the propensity score-matched pairs (n = 78), we found that platelet-rich plasma group still showed significant improvement over the hyaluronic acid group in arthroplasty rate (12.8% vs 41.0%, p = 0.010), Visual Analogue Scale and Western Ontario and McMaster Universities Osteoarthritis Index scores, but not in the range of motion, during the mean follow-up of 16.7 months.

CONCLUSION

Intra-articular injections of platelet-rich plasma associated with better outcomes than hyaluronic acid in knee osteoarthritis. Platelet-rich plasma might prolong the time to arthroplasty and provide a valid therapeutic option in selected patients with knee osteoarthritis not responding to conventional treatments. Further larger studies are needed to validate this promising treatment modality.

Emerging Orthobiologic Techniques and the Future

The future of orthopedic surgery appears to be intimately associated with the development of orthobiologics to facilitate healing and the treatment of multiple disease processes. The orthopedic community should understand developmental processes to ensure that products are adequately studied and the effects are fully known before widespread implementation in the clinical setting. Technologies that embrace this paradigm will impact the field the most.

Problems persist in reporting of methods and results for the WOMAC measure in hip and knee osteoarthritis trials

Purpose

The Western Ontario and McMaster Universities Arthritis Index (WOMAC) is a commonly used outcome measure for osteoarthritis. There are different versions of the WOMAC (Likert, visual analogue or numeric scales). A previous review of trials published before 2010 found poor reporting and inconsistency in how the WOMAC was used. This review explores whether these problems persist.

Methods

This systematic review included randomised trials of hip and/or knee osteoarthritis published in 2016 that used the WOMAC. Data were extracted on the version used, score range, analysis and results of the WOMAC, and whether these details were clearly reported.

Results

This review included 62 trials and 41 reported the WOMAC total score. The version used and item range for the WOMAC total score were unclear in 44% (n = 18/41) and 24% (n = 10/41) of trials, respectively. The smallest total score range was 0–10 (calculated by averaging 24 items scored 0–10); the largest was 0–2400 (calculated by summing 24 items scored 0–100). All trials reported the statistical analysis methods but only 29% reported the between-group mean difference and 95% confidence interval.

Conclusion

Details on the use and scoring of the WOMAC were often not reported. We recommend that trials report the version of the WOMAC and the score range used. The between-group treatment effect and corresponding confidence interval should be reported. If all the items of the WOMAC are collected, the total score and individual subscale scores should be presented. Better reporting would facilitate the interpretation, comparison and synthesis of the WOMAC score in trials.

Electronic supplementary material

The online version of this article (10.1007/s11136-018-1978-1) contains supplementary material, which is available to authorized users.

Efficacy of intra-articular injections of platelet-rich plasma as a symptom- and disease-modifying treatment for knee osteoarthritis - the RESTORE trial protocol

Background

Knee osteoarthritis (OA) causes substantial pain, physical dysfunction and impaired quality of life. There is no cure for knee OA, and for some people, the disease may involve progressive symptomatic and structural deterioration over time. Platelet-rich plasma (PRP) is a therapeutic agent that aims to address underlying biological processes responsible for OA pathogenesis. As such, it has the potential to improve both symptoms and joint structure. The aim of this clinical trial is to determine whether a series of injections of PRP into the knee joint will lead to a significantly greater reduction in knee pain, and less loss of medial tibial cartilage volume over 12 months when compared to a series of placebo saline injections in people with knee OA.

Methods

This will be a two-group, superiority, randomised, participant-, interventionist- and assessor-blinded, placebo-controlled trial. Two hundred and eighty-eight participants aged over 50 years with painful knee OA and mild to moderate structural change on x-ray (Kellgren and Lawrence grade 2 and 3) will be randomly allocated to receive either three PRP injections or three normal saline injections into the knee joint at weekly intervals. The primary outcomes will be 12-month change in average overall knee pain severity (numeric rating scale) and medial tibial cartilage volume (magnetic resonance imaging (MRI)). Secondary outcomes include additional measures of knee pain and other symptoms, function in daily living and sport and recreation, quality of life, participant-perceived global ratings of change, and other MRI structural outcomes including meniscal and cartilage morphology, synovitis, effusion, bone marrow lesions and cartilage defects. A range of additional measures will be recorded, and a separate health economic evaluation will be performed.

Discussion

The findings from this study will help determine whether PRP improves both clinical and structural knee OA outcomes over 12 months when compared to a series of placebo saline injections.

Trial registration

Australian New Zealand Clinical Trials Registry reference: ACTRN12617000853347. Prospectively registered 9th of June 2017.

Electronic supplementary material

The online version of this article (10.1186/s12891-018-2205-5) contains supplementary material, which is available to authorized users.

Current Concepts and Future Directions of Minimally Invasive Treatment for Knee Pain

PURPOSE OF REVIEW

The purpose of this paper is to review the percutaneous interventions available for the treatment of osteoarthrosis of the knee that address pain and prolong the time to arthroplasty.

RECENT FINDINGS

Corticosteroid injection and viscosupplementation have been the most studied, but there is still no consensus about their value. Thermal nerve ablation, including both radiofrequency ablation and cryoneurolysis, is a promising new modality of therapy that may increase in clinical use given current data showing favorable outcomes. Of the future therapies that are currently under investigation, synovial embolization via the geniculate arteries represents an exciting new approach that may soon be available clinically. There are various percutaneous interventions available for the treatment of osteoarthrosis of the knee that address pain and prolong the time to arthroplasty.

Regenerative Sports Medicine: Past, Present, and Future (Adapted From the PASSOR Legacy Award Presentation; AAPMR; October 2016)

Regenerative medicine has shown dramatic expanse and evolution in the past decade. Within that milieu, physiatrists are taking an active role in research, clinical care delivery, and education. The purpose of this review is to provide a balance among evidence, theory, experience, clinical trends, and the foreseeable future. We focus on the literature that reports the research with the best methodology in each practice area, recognizing that the level of evidence varies substantially among different treatment modalities and conditions. The following elements are included: an overview of the evolution of currently available regenerative techniques, evidence base for each available modality (prolotherapy, platelet rich plasma, bone marrow aspirate concentrate and stem cells, adipose-derived stem cells, and amniotic tissue products), general principles in the application of these treatments, and discussion and a vision of what lies ahead. We expect that practitioners will use this review to facilitate clinical decision making and to provide a core knowledge base to assist when counseling patients. LEVEL OF EVIDENCE: IV.

Platelet-rich Plasma for Skin Rejuvenation and Treatment of Actinic Elastosis in the Lower Eyelid Area

Background

Treatment of the lower eyelid region to rejuvenate the skin or treat actinic elastosis often proves difficult. Established treatment options, such as hyaluronic acid injections, botulinum toxin injections, microneedling, skin resurfacing (microdermabrasion, chemical peel (exfoliation), laser treatment), as well as blepharoplasties and autologous fat transfers, can be associated with significant risks and increased patient burden. Furthermore, they may not be effective for treating the signs of skin aging or actinic elastosis, including dark rings under the eyes, a lack of volume and cutis laxa. A minimally invasive treatment approach which visibly improves the above-mentioned conditions and which involves minimal risk and patient burden would be a desirable alternative.

Materials & methods

Twenty patients were treated a total of three times at monthly intervals with PRP (platelet-rich plasma). The patients were examined on the days of treatment and one month after the third injection. The PRP was obtained directly prior to treatment using the Arthrex ACP double syringe at the point of care. The injections (2 ml PRP per side) were administered laterally using 27 G 38 mm cannulas. Accurate photographic documentation and skin elasticity measurements using a cutometer were performed to objectify the subjective assessments from the patient and practitioner questionnaires.

Results

A progressive improvement in the esthetic outcome and a high level of patient satisfaction were determined. The cutometer measurements showed a statistically significant higher level of skin firmness (due to increased collagen production) and a statistically significant increase in skin elasticity (thanks to increased elastin production). Other than the anticipated visible swelling directly after the PRP injection, no other undesirable side effects or complications occurred. The typical burning sensation during the injection had not been reported.

Conclusion

The results indicate that a series of PRP injections in the lower eyelid region is a safe, efficient, virtually pain-free, simple and rapid treatment option for an area with otherwise limited treatment alternatives.

How far have biological therapies come in regenerative sports medicine?

INTRODUCTION

Regular engagement in sports produces many health benefits, but also exposes to increased injury risk. The quality of medical care available is crucial not only for sports trauma but also to avoid overuse syndromes and post-traumatic degenerative conditions.

AREAS COVERED

We provide background information on some clinical needs in sport injuries and describe the main families of biological products used in clinical practice. We also discuss limitations of the current clinical experience.

EXPERT OPINION

Sport and exercise impairment affects different segments of the population with different needs. The exceptional demands of elite athletes and subsequent media coverage have created hype around regenerative therapies. Statistical evidence, whether weak (cell products) or moderate (PRPs), is not enough to drive medical decisions because of the heterogeneity of the biological products available and their application procedures. Moreover, the specific needs of the different segments of the population along with the available clinical evidence for each musculoskeletal condition should be considered in the decision-making process. There is urgent need to develop regenerative protocols combined with post-intervention rehabilitation, and gather meaningful clinical data on the safety and efficacy of these interventions in the different populations segments.

Leukocyte-Poor Platelet-Rich Plasma-Derived Growth Factors Enhance Human Fibroblast Proliferation In Vitro

Background

Leukocyte-poor platelet-rich plasma (LP-PRP) from peripheral blood is currently used as a concentrated source of growth factors to stimulate repair at sites of soft tissue injury. Fibroblasts are primary mediators of wound healing. Thus, we aimed to assess the positive effect of LP-PRP on human fibroblast proliferation in vitro.

Methods

LP-PRP was prepared from 49 donors. The fibroblasts were seeded, and at 24 hours after seeding, 1 × 10⁷/10 µL LP-PRP was added once to each well. The cells were harvested 10 times during study period at our planned points, and we examined cell proliferation using the water-soluble tetrazolium salt-1 assay. We collected the supernatants and measured the amount of growth factors such as platelet-derived growth factor (PDGF)-AB/BB, insulin-like growth factor-1 (IGF-1), transforming growth factor-β1 (TGF-β1), and vascular endothelial growth factor (VEGF), which are known to be involved in wound healing processes, by multiplex assay.

Results

Human fibroblasts treated with LP-PRP showed a significant increase in proliferation when compared to untreated controls (p < 0.001 at days 4, 6, and 8). Multiplex cytokine assays revealed various secretion patterns. PDGF-AB/BB appeared at early time points and peaked before fibroblast proliferation. IGF-1 and TGF-β1 secretion gradually increased and peaked on days 4 and 6 post-treatment. The early VEGF concentration was lower than the concentration of other growth factors but increased along with cell proliferation.

Conclusions

Platelets in LP-PRP release growth factors such as PDGF, IGF-1, TGF-β1 and VEGF, and these growth factors have a promoting effect for human fibroblast proliferation, one of the important mediators of wound healing. These results suggest that growth factors derived from LP-PRP enhance the proliferation of human fibroblast.

Intra-ligamentary autologous conditioned plasma and healing response to treat partial ACL ruptures

INTRODUCTION

Conservative treatment of partial ACL ruptures is associated with a high failure rate, and often patients undergo ACL reconstruction. ACL preservation by trephination of the ACL origin and application of Autologous Conditioned Plasma (ACP) seems to be an intriguing new treatment option to favour ACL tissue healing and avoid traditional reconstruction. The aim of this study was to describe the mid-term outcomes of this new ACL preserving technique.

MATERIALS AND METHODS

Twenty-four patients (mean age 41.8 years) affected by partial rupture of one or both ACL bundles were included in the present trial. The partial ACL tears were arthroscopically assessed and classified according to a new five step grading system. All patients were treated by trephination of the femoral ACL stump and intra-ligamentary application of ACP. The postoperative outcome was evaluated by both subjective scores and stability testing up to a mean of 25.1 months' follow-up. Adverse events and failure rate were also documented.

RESULTS

Clinical outcome was good to excellent with IKDC subjective 82.7 (SD 11.8), Lysholm 87.6 (SD 8.1), Tegner 5.3 (SD 2.1), Cincinnati 88.7 (SD 14.8). The failure rate (i.e. persisting knee instability assessed clinically or by rolimeter) was 12.5%. At objective measurements, knee joints showed a firm endpoint in Lachman test, negative pivot shift phenomenon and a significant reduction in AP-laxity compared to pre-operative status by rolimeter testing (p = 0.002). Return to sport practice was achieved after mean 4.8 months (SD 4.1).

CONCLUSIONS

ACL stump trephination and concomitant intra-ligamentary application of ACP revealed promising results at mid-term follow-up to treat partial ACL lesions.

Facilitated recruitment of mesenchymal stromal cells by bone marrow concentrate and platelet rich plasma

BACKGROUND

Biologics containing growth factors are frequently used to enhance healing after musculoskeletal injuries. One mechanism of action is thought to be though the ability of biologics to induce homing and migration of endogenous mesenchymal stromal cells (MSCs) to a target tissue. However, the ability of biologics to stimulate chemotaxis (directed migration of cells) and chemokinesis (increase rate of cell migration) of MSCs is unknown.

HYPOTHESIS/PURPOSE

The aim of this study was to directly compare the ability of biologics including platelet rich plasma (PRP) and bone marrow concentrate (BMC) to induce MSC migration. The hypothesis was that leukocyte-low platelet rich plasma (Llo PRP) would induce migration to a greater extent than leukocyte-high platelet rich plasma (Lhi PRP) or BMC.

METHODS

Bone marrow-derived MSCs were isolated from 8 horses. Migration of MSCs toward a biologic (BMC, Llo PRP, and Lhi PRP) or the positive control platelet derived growth factor (PDGF) was continuously traced and measured for 24hrs using time-lapse microscopy and a microfluidics device. Cell migration, chemotaxis and chemokinesis were determined by measurements of displacement, number of cells migrated, and cell flux.

RESULTS

All biologics resulted in a significantly greater percentage of MSCs migrated compared to the positive control (PDGF). MSCs migrated further toward BMC compared to Llo PRP. Cell migration, measured as cell flux, was greater toward BMC and Lhi PRP than Llo PRP.

CONCLUSION

The biologics BMC and Lhi PRP elicit greater chemotaxis and chemokinesis of MSCs than Llo PRP. However, all biologics recruited the same number of MSCs suggesting that differences in other regenerative effects, such as growth factor concentration, between biologics should be strongly considered when choosing a biologic for treatment of musculoskeletal injuries. The results of this study have the potential to reduce the need, risks, and costs associated with MSC culture and delivery.

Osteoarthritis year in review 2017: clinical

This review is based on a systematic review of the literature relevant to clinical topics in osteoarthritis (OA) performed for the time period February 22, 2016 to April 1, 2017. A PubMed search using the terms "osteoarthritis" and "treatment or epidemiology" returned over 800 papers, of which 57 are reviewed here, with inclusion primarily based on relevance to clinical OA. Epidemiologic studies in this time frame focused on the incidence and prevalence of OA, comorbidities and mortality in relation to OA (particularly obesity and cardiovascular disease), and multiple joint involvement. Papers on therapeutic approaches to OA considered: non-pharmacologic options, a number of topical, oral, and intra-articular therapies, as well as the cost-effectiveness of some OA treatments. There an enormous need to identify novel strategies to reduce the impact of this highly prevalent and debilitating condition.

Intra-articular Injections of Platelet-Rich Plasma Releasate Reduce Pain and Synovial Inflammation in a Mouse Model of Osteoarthritis

BACKGROUND

Osteoarthritis (OA) is a degenerative joint disease leading to pain and disability for which no curative treatment exists. A promising biological treatment for OA is intra-articular administration of platelet-rich plasma (PRP). PRP injections in OA joints can relieve pain, although the exact working mechanism is unclear.

PURPOSE

To examine the effects of PRP releasate (PRPr) on pain, cartilage damage, and synovial inflammation in a mouse OA model.

STUDY DESIGN

Controlled laboratory study.

METHODS

OA was induced unilaterally in the knees of male mice (n = 36) by 2 intra-articular injections of collagenase at days -7 and -5. At day 0, pain was measured by registering weight distribution on the hindlimbs, after which mice were randomly divided into 2 groups. Mice received 3 intra-articular injections of PRP or saline in the affected knee. Seven mice per group were euthanized at day 5 for assessment of early synovial inflammation and cartilage damage. Pain in the remaining mice was registered for a total of 3 weeks. These mice were euthanized at day 21 for assessment of cartilage damage and synovial inflammation on histological evaluation. Antibodies against iNOS, CD163, and CD206 were used to identify different subtypes of macrophages in the synovial membrane.

RESULTS

Mice in the PRPr group increased the distribution of weight on the affected joint in 2 consecutive weeks after the start of the treatment ( P < .05), whereas mice in the saline group did not. At day 21, PRPr-injected knees had a thinner synovial membrane ( P < .05) and a trend toward less cartilage damage in the lateral joint compartment ( P = .053) than saline-injected knees. OA knees treated with saline showed less anti-inflammatory (CD206+ and CD163+) cells at day 5 than healthy knees, an observation that was not made in the PRPr-treated group. A higher level of pain at day 7 was associated with a thicker synovial membrane at day 21. The presence of CD206+ cells was negatively associated with synovial membrane thickness.

CONCLUSION

In a murine OA model, multiple PRPr injections reduced pain and synovial thickness, possibly through modulation of macrophage subtypes.

CLINICAL RELEVANCE

PRPr injections in early OA or shortly after joint trauma can reduce pain and synovial inflammation and may inhibit OA development in patients.

Comparison of hyaluronic acid and PRP intra-articular injection with combined intra-articular and intraosseous PRP injections to treat patients with knee osteoarthritis

The aim of this study was to evaluate the benefit provided by intraosseous infiltration combined with intra-articular injection of platelet-rich plasma to treat mild and moderate stages of knee joint degeneration (Kellgren-Lawrence score II-III) compared with other treatments, specifically intra-articular injection of PRP and of HA. Eighty-six patients with grade II to grade III knee OA according to the Kellgren-Lawrence classification were randomly assigned to intra-articular combined with intraosseous injection of PRP (group A), intra-articular PRP (group B), or intra-articular HA (group C). Patients in group A received intra-articular combined with intraosseous injection of PRP (administered twice, 2 weeks apart). Patients in group B received intra-articular injection of PRP every 14 days. Patients in group C received a series of five intra-articular injections of HA every 7 days. All patients were evaluated using the Visual Analogue Scale (VAS) and Western Ontario and McMaster Universities (WOMAC) score before the treatment and at 1, 3, 6, 12, and 18 months after treatment. There were significant improvements at the end of the 1st month. Notably, group A patients had significantly superior VAS and WOMAC scores than were observed in groups B and C. The VAS scores were similar in groups B and group C after the 6th month. Regarding the WOMAC scores, groups B and C differed at the 1st, 3rd, 6th, and 12th months; however, no significant difference was observed at the 18th month. The combination of intraosseous with intra-articular injections of PRP resulted in a significantly superior clinical outcome, with sustained lower VAS and WOMAC scores and improvement in quality of life within 18 months.

Clinical Outcomes of Knee Osteoarthritis Treated With an Autologous Protein Solution Injection: A 1-Year Pilot Double-Blinded Randomized Controlled Trial

BACKGROUND

Osteoarthritis (OA) is a debilitating disease resulting in substantial pain and functional limitations. A novel blood derivative has been developed to concentrate both growth factors and antagonists of inflammatory cytokines, with promising preliminary findings in terms of safety profile and clinical improvement.

PURPOSE

To investigate if one intra-articular injection of autologous protein solution (APS) can reduce pain and improve function in patients affected by knee OA in a multicenter, randomized, double-blind, saline-controlled study.

STUDY DESIGN

Randomized controlled trial; Level of evidence, 2.

METHODS

Forty-six patients with unilateral knee OA (Kellgren-Lawrence 2 or 3) were randomized into the APS group (n = 31), which received a single ultrasound-guided injection of APS, and the saline (control) group (n = 15), which received a single saline injection. Patient-reported outcomes and adverse events were collected at 2 weeks and at 1, 3, 6, and 12 months through visual analog scale (VAS), Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), Knee injury and Osteoarthritis Outcome Score (KOOS), Short Form-36 (SF-36), Clinical Global Impression of Severity/Change (CGI-S/C), Patient Global Impression of Severity/Change (PGI-S/C), and Outcome Measures in Rheumatology-Osteoarthritis Research Society International (OMERACT-OARSI) responder rate. Imaging evaluation was also performed with radiograph and magnetic resonance imaging (MRI) before and after treatment (12 months and 3 and 12 months, respectively).

RESULTS

The safety profile was positive, with no significant differences in frequency and severity of adverse events between groups. The improvement from baseline to 2 weeks and to 1, 3, and 6 months was similar between treatments. At 12 months, improvement in WOMAC pain score was 65% in the APS group and 41% in the saline group ( P = .02). There were no significant differences in VAS pain improvement between groups. At 12 months, APS group showed improved SF-36 Bodily Pain subscale ( P = .0085) and Role Emotional Health subscale ( P = .0410), as well as CGI-C values ( P = .01) compared with saline control. Significant differences between groups were detected in change from baseline to 12 months in bone marrow lesion size as assessed on MRI and osteophytes in the central zone of the lateral femoral condyle, both in favor of the APS group ( P = .041 and P = .032, respectively). There were no significant differences between APS and control groups in other measured secondary endpoints.

CONCLUSION

This study provides evidence to support the safety and clinical improvement at 1-year follow-up of a single intra-articular injection of APS in patients affected by knee OA. Treatment with APS or a saline injection provided significant pain relief over the course of the study with differences becoming apparent at between 6 and 12 months after treatment.

TRIAL REGISTRATION

NCT02138890 ( ClinicalTrials.gov identifier).

Intra-articular injection of expanded autologous bone marrow mesenchymal cells in moderate and severe knee osteoarthritis is safe: a phase I/II study

Background

Knee osteoarthritis (KOA) is a major health problem especially in the aging population. There is a need for safe treatment that restores the cartilage and reduces the symptoms. The use of stem cells is emerging as a possible option for the moderate and severe cases. This study aimed at testing the safety of autologous bone marrow mesenchymal stem cells (BM-MSCs) expanded in vitro when given intra-articularly to patients with stage II and III KOA. As a secondary end point, the study tested the ability of these cells to relieve symptoms and restore the knee cartilage in these patients as judged by normalized knee injury and Osteoarthritis Outcome Score (KOOS) and by magnetic resonance imaging (MRI).

Methods

Thirteen patients with a mean age of 50 years suffering from KOA stages II and III were given two doses of BM-MSCs 1 month apart totaling 61 × 10⁶ ± 0.6 × 10⁶ by intra-articular injection in a phase I prospective clinical trial. Each patient was followed for a minimum of 24 months for any adverse events and for clinical outcome using normalized KOOS. Cartilage thickness was assessed by quantitative MRI T2 at 12 months of follow-up.

Results

No severe adverse events were reported up to 24 months follow-up. Normalized KOOS improved significantly. Mean knee cartilage thickness measured by MRI improved significantly.

Conclusion

BM-MSCs given intra-articularly are safe in knee osteoarthrosis. Despite the limited number of patients in this study, the procedure described significantly improved the KOOS and knee cartilage thickness, indicating that they may enhance the functional outcome as well as the structural component.

Trial registration

ClinicalTrials.gov, NCT02118519

Platelet-Rich Plasma Supports Proliferation and Redifferentiation of Chondrocytes during In Vitro Expansion

Articular cartilage regeneration is insufficient to restore sports injuries or defects that can occur from trauma. Treatment options for cartilage repair include autologous chondrocyte implantation (ACI) by isolation, expansion, and reimplantation of healthy donor chondrocytes. Chondrocyte expansion onto 2D substrates leads to dedifferentiation and loss of the cellular phenotype. We aimed to overcome the state of dedifferentiation by biochemical stimuli with platelet derivatives such as platelet-rich plasma (PRP) and hyperacute serum (HAS) to achieve sufficient cell numbers in combination with variable oxygen tension. Human articular chondrocytes from osteoarthritic (OA) cartilage chondrocytes were switched from 10% FCS supplementation to either 10% PRP or 10% HAS after initial passaging for further experiments under normoxic (20% O₂) or hypoxic (1% O₂) conditions. An XTT assay measured the effect of PRP or HAS on the cell proliferation at 3, 6, and 9 days. The chondrogenic redifferentiation potential of dedifferentiated chondrocytes was determined with reverse transcriptase quantitative real-time PCR for markers of expression for type II collagen (COL2A1), type I collagen (COL1A1), and matrix metalloproteinases MMP3, matrix metalloproteinase 13 (MMP13) at 24 and 72 h. Measured protein levels of 100% PRP or HAS by multiplex quantification revealed basic fibroblast growth factor, G-CSF, and PDGF were significantly higher in PRP than in HAS (p < 0.05) but LEPTIN levels did not differ. The quantified protein levels did not differ when isolated from same donors at a different time. Chondrocyte proliferation indicated that supplementation of 10% HAS enhanced the proliferation rate compared to 10% PRP or 10% FCS at 6 and 9 days significantly (p < 0.05). mRNA levels for expression of COL1A1 were significantly downregulated (p < 0.05) when cultured with 10% PRP than 10% HAS or 10% FCS under normoxic/hypoxic conditions. COL2A1 was significantly upregulated (p < 0.05) in PRP than 10% HAS or 10% FCS. MMP3 expression was downregulated after 72 h under all conditions. MMP13 was upregulated with 10% PRP at both 24 and 72 h but significantly downregulated under hypoxia (1% O₂) for all circumstances. While HAS has its effect on chondrocyte proliferation, PRP enhances both proliferation and redifferentiation of dedifferentiated chondrocytes. PRP can replace standard usage of FCS for chondrogenic priming and expansion as implications for clinical use such as ACI procedures.

Platelet-Rich Plasma for the Management of Hip and Knee Osteoarthritis

PURPOSE OF REVIEW

Knee and hip osteoarthritis (OA) are major public health problems worldwide causing pain, disability and impaired quality of life. This narrative paper discusses platelet-rich plasma (PRP) as a treatment for hip and knee OA, with a focus on evidence from randomised controlled trials (RCTs).

RECENT FINDINGS

Since the first RCT of PRP in 2012, there has been 15 RCTs in knee OA and three in hip OA, mostly comparing PRP to another intra-articular injection therapy, hyaluronic acid. All studies are of low to moderate methodological quality and use variable PRP protocols. In general, results showed that PRP is a safe treatment with potential to provide symptomatic benefit for OA at least in the short term (up to 12 months). Younger patients with less severe disease may be more responsive. There are no RCTs investigating the effects of PRP on OA structural changes. No definitive conclusions can be made about the effects of PRP in OA given methodological concerns and considerable heterogeneity between studies. Further high-quality research is needed to establish the clinical and cost-effectiveness of PRP, the patients most likely to benefit and the optimal PRP protocol.

Biologic injections for osteoarthritis and articular cartilage damage: can we modify disease?

OBJECTIVE

The purpose of the present investigation is to conduct a systematic review of the literature to review the clinical results of platelet rich plasma (PRP) and mesenchymal stem cell treatments (MSC) (biologics) for articular cartilage lesions and osteoarthritis of the knee.

METHODS

A search of the PubMed, EMBASE, and Cochrane databases was performed to identify studies involving biologic therapy for osteoarthritis or osteochondral defects. Only Level I-III clinical trials with at least 3-month follow-up were included. Outcome data was gathered on any patient-completed surveys, 2nd look arthroscopy, follow-up imaging, biopsy/histology results, and any adverse effects of treatment.

RESULTS

Thirty-three articles met our inclusion criteria. There was a total of 21 PRP studies in the study. All PRP studies showed clinical improvement with PRP therapies in outcomes surveys measuring patient satisfaction, pain, and function. Two studies reported no significant difference in improvement compared to hyaluronic acid (HA). Similarly, the 7/9 MSC studies showed improvement. One study found BM-MSC implantation was not significantly superior to matrix assisted chondrocyte implantation (MACI), while one reported peripheral blood stem cells (PBSC) did not significantly improve outcomes over HA. Of the three studies looking at a combination of MSC/PRP, two found MSC/PRP combination did not improve outcomes compared to MSC or PRP therapy alone. The one PRP study that had a 2nd look arthroscopy reported increases cartilage regeneration with PRP. All 8 MSC studies with follow-up MRI and all 7 MSC studies with 2nd look arthroscopy showed improvement in cartilage regeneration in terms of coverage, fill of the defect, and/or firmness of the new cartilage.

CONCLUSION

Current data suggests that, of the two treatments, MSC provides more significant disease modifying effect; however, further research needs to be done to compare these two treatments and determine if there is a synergetic effect when combined.

Percutaneous Fat Transfer to Treat Knee Osteoarthritis Symptoms: Preliminary Results

Purpose  This study aims to evaluate the safety and efficacy of autologous aspirated and purified fat tissue injected percutaneously into the knee joint for the treatment of symptomatic osteoarthritis (OA). Methods  We reviewed 30 patients, who received an autologous percutaneous fat injection for the treatment of knee OA, from January 2012 to March 2015. Mean patients' age was 63.3 ± 5.3 years (range, 50-80 years). Body mass index was 25.1 ± 1.7. Clinical evaluation was based on pain visual analog scale (VAS) and WOMAC score for functional and subjective assessment. We also noted the adverse reactions and the consumption of nonsteroidal anti-inflammatory drugs in the posttreatment period. Results  All patients reported improvements with respect to pain: average VAS was 7.7 ± 1.2 at baseline, 5.2 ± 0.2 at 1-month follow-up, and 4.3 ± 1 at 3-month follow-up. A slight deterioration (5.0 ± 1.1) was evidenced at 1 year. Total WOMAC score was 89.9 ± 1.7 at baseline, 66.3 ± 1 at 1 month, 68.6 ± 1.7 at 3 months, and 73.2 ± 1.8 at 12 months of follow-up. Conclusion  Our preliminary findings suggest that autologous percutaneous fat injections are a valid treatment option for knee OA. Level of Evidence  Level IV, therapeutic case series.

Osteochondral Allograft Transplantation for Treatment of Focal Patellar Osteochondral Lesion

Patellar osteochondral lesions are common and particularly disabling injuries that can affect young and highly active patients. If enough functional impairment, ranging from difficulty climbing stairs to pain with squatting, is present, surgical treatment may be warranted. For the treatment of these lesions, various techniques have been described, including autologous osteochondral transplantation, as well as microfracture surgery. However, these are not without disadvantages. Although morbidity is noted in cases of autologous osteochondral transplantation, uncertain and possibly unsustainable results are associated with the microfracture procedure. Therefore, we present an alternative surgical treatment option for this pathology. The objective of this Technical Note is to describe our preferred approach for an osteochondral allograft transplant procedure to treat a focal patellar osteochondral lesion.

Case series of ultrasound-guided platelet-rich plasma injections for sacroiliac joint dysfunction

BACKGROUND

Two-thirds of adults worldwide will experience low back pain at some point in their life. In the following case series, we present four patients with sacroiliac (SI) joint instability and severe chronic low back pain, which was refractory to other treatment modalities.

OBJECTIVE

We investigated the efficacy of platelet-rich plasma (PRP) injections, a novel orthobiologic therapy, for reducing SI joint pain, improving quality of life, and maintaining a clinical effect.

METHODS

Short-form McGill Pain Questionnaire (SFM), Numeric Rating Scale (NRS), and Oswestry Low Back Pain and Disability Index were used for evaluation of treatment at pretreatment, 12-months and 48-months after treatment.

RESULTS

At follow-up 12-months post-treatment, pooled data from all patients reported a marked improvement in joint stability, a statistically significant reduction in pain, and improvement in quality of life. The clinical benefits of PRP were still significant at 4-years post-treatment.

CONCLUSIONS

Platelet-rich plasma therapy exhibits clinical usefulness in both pain reduction and for functional improvement in patients with chronic SI joint pain. The improvement in joint stability and low back pain was maintained at 1- and 4-years post-treatment.

Efficacy of Platelet-Rich Plasma in the Treatment of Knee Osteoarthritis: A Meta-analysis of Randomized Controlled Trials

PURPOSE

To use meta-analysis techniques to evaluate the efficacy and safety of platelet-rich plasma (PRP) injections for the treatment knee of osteoarthritis (OA).

METHODS

We performed a systematic literature search in PubMed, Embase, Scopus, and the Cochrane database through April 2016 to identify Level I randomized controlled trials that evaluated the clinical efficacy of PRP versus control treatments for knee OA. The primary outcomes were Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) pain and function scores. The primary outcomes were compared with their minimum clinically important differences (MCID)-defined as the smallest difference perceived as important by the average patient.

RESULTS

We included 10 randomized controlled trials with a total of 1069 patients. Our analysis showed that at 6 months postinjection, PRP and hyaluronic acid (HA) had similar effects with respect to pain relief (WOMAC pain score) and functional improvement (WOMAC function score, WOMAC total score, International Knee Documentation Committee score, Lequesne score). At 12 months postinjection, however, PRP was associated with significantly better pain relief (WOMAC pain score, mean difference -2.83, 95% confidence interval [CI] -4.26 to -1.39, P = .0001) and functional improvement (WOMAC function score, mean difference -12.53, 95% CI -14.58 to -10.47, P  < .00001; WOMAC total score, International Knee Documentation Committee score, Lequesne score, standardized mean difference 1.05, 95% CI 0.21-1.89, P = .01) than HA, and the effect sizes of WOMAC pain and function scores at 12 months exceeded the MCID (-0.79 for WOMAC pain and -2.85 for WOMAC function score). Compared with saline, PRP was more effective for pain relief (WOMAC pain score) and functional improvement (WOMAC function score) at 6 months and 12 months postinjection, and the effect sizes of WOMAC pain and function scores at 6 months and 12 months exceeded the MCID. We also found that PRP did not increase the risk of adverse events compared with HA and saline.

CONCLUSIONS

Current evidence indicates that, compared with HA and saline, intra-articular PRP injection may have more benefit in pain relief and functional improvement in patients with symptomatic knee OA at 1 year postinjection.

LEVEL OF EVIDENCE

Level I, meta-analysis of Level I studies.

Platelet-Rich Plasma Injections for Advanced Knee Osteoarthritis: A Prospective, Randomized, Double-Blinded Clinical Trial

Background:

Intra-articular injections of platelet-rich plasma (PRP) to treat symptoms of knee osteoarthritis (OA) have been successfully used in young patients and in the early stages of disease. No previous studies have analyzed outcomes of PRP injections during the late stages.

Hypothesis:

PRP reduces pain and leads to a more effective and lasting functional recovery than corticosteroid with local anesthetic.

Study Design:

Randomized controlled trial; Level of evidence, 2.

Methods:

A total of 75 patients with symptomatic knee OA (Kellgren-Lawrence grade 3 to 4) were enrolled in this study between August 2013 and July 2014. Patients were randomized to treatment either with a single leukocyte-reduced PRP or corticosteroid intra-articular injection. The primary variable was visual analog scale assessment at 1 month. Secondary outcomes were the Knee injury and Osteoarthritis Outcome Score (KOOS) and Short Form–36 (SF-36) at 1, 3, and 6 months after treatment. Patient satisfaction at final follow-up was assessed. Both groups were homogeneous and comparable in baseline characteristics.

Results:

All variables improved in both groups. Statistical differences between groups were not found for the majority of the outcome variables, although the magnitude of improvements tended to be greater in the PRP group. Quality-of-life differences between values at 3 and 6 months versus baseline increased significantly more in the study group (P = .05 and .03, respectively), and so did general health perception differences at 6 months (P = .018).

Conclusion:

A single PRP intra-articular injection is effective for relieving pain and improving activities of daily living and quality of life in late-stage knee OA. For patients with late-stage knee OA who are 67 years or older, 1 intra-articular injection of PRP has similar results to 1 shot of corticosteroid.

The temporal effect of platelet-rich plasma on pain and physical function in the treatment of knee osteoarthritis: systematic review and meta-analysis of randomized controlled trials

Background

Quite a few randomized controlled trials (RCTs) investigating the efficacy of platelet-rich plasma (PRP) for treatment of knee osteoarthritis (OA) have been recently published. Therefore, an updated systematic review was performed to evaluate the temporal effect of PRP on knee pain and physical function.

Methods

Pubmed, Embase, Cochrane library, and Scopus were searched for human RCTs comparing the efficacy and/or safety of PRP infiltration with other intra-articular injections. A descriptive summary and quality assessment were performed for all the studies finally included for analysis. For studies reporting outcomes concerning Western Ontario and McMaster Universities Arthritis Index (WOMAC) or adverse events, a random-effects model was used for data synthesis.

Results

Fourteen RCTs comprising 1423 participants were included. The control included saline placebo, HA, ozone, and corticosteroids. The follow-up ranged from 12 weeks to 12 months. Risk of bias assessment showed that 4 studies were considered as moderate risk of bias and 10 as high risk of bias. Compared with control, PRP injections significantly reduced WOMAC pain subscores at 3, 6, and 12 months follow-up (p = 0.02, 0.004, <0.001, respectively); PRP significantly improved WOMAC physical function subscores at 3, 6, and 12 months (p = 0.002, 0.01, <0.001, respectively); PRP also significantly improved total WOMAC scores at 3, 6 and 12 months (all p < 0.001); nonetheless, PRP did not significantly increased the risk of post-injection adverse events (RR, 1.40 [95% CI, 0.80 to 2.45], I² = 59%, p = 0.24).

Conclusions

Intra-articular PRP injections probably are more efficacious in the treatment of knee OA in terms of pain relief and self-reported function improvement at 3, 6 and 12 months follow-up, compared with other injections, including saline placebo, HA, ozone, and corticosteroids.

Review registration

PROSPERO CRD42016045410. Registered 8 August 2016.

Electronic supplementary material

The online version of this article (doi:10.1186/s13018-017-0521-3) contains supplementary material, which is available to authorized users.